using GPG; using Xmpp; namespace Dino.Plugins.OpenPgp { private const string NS_URI = "jabber:x"; private const string NS_URI_ENCRYPTED = NS_URI + ":encrypted"; private const string NS_URI_SIGNED = NS_URI + ":signed"; public class Module : XmppStreamModule { public static Xmpp.ModuleIdentity IDENTITY = new Xmpp.ModuleIdentity(NS_URI, "0027_current_pgp_usage"); public signal void received_jid_key_id(XmppStream stream, Jid jid, string key_id); private string? signed_status = null; private Key? own_key = null; private ReceivedPipelineDecryptListener received_pipeline_decrypt_listener = new ReceivedPipelineDecryptListener(); public Module(string? own_key_id = null) { set_private_key_id(own_key_id); } public void set_private_key_id(string? own_key_id) { if (own_key_id != null) { try { own_key = GPGHelper.get_private_key(own_key_id); if (own_key == null) print("PRIV KEY NULL\n"); } catch (Error e) { } if (own_key != null) { signed_status = gpg_sign("", own_key); } } } public bool encrypt(MessageStanza message, GPG.Key[] keys) { string? enc_body = gpg_encrypt(message.body, keys); if (enc_body != null) { message.stanza.put_node(new StanzaNode.build("x", NS_URI_ENCRYPTED).add_self_xmlns().put_node(new StanzaNode.text(enc_body))); message.body = "[This message is OpenPGP encrypted (see XEP-0027)]"; Xep.ExplicitEncryption.add_encryption_tag_to_message(message, NS_URI_ENCRYPTED); return true; } return false; } public override void attach(XmppStream stream) { stream.get_module(Presence.Module.IDENTITY).received_presence.connect(on_received_presence); stream.get_module(Presence.Module.IDENTITY).pre_send_presence_stanza.connect(on_pre_send_presence_stanza); stream.get_module(MessageModule.IDENTITY).received_pipeline.connect(received_pipeline_decrypt_listener); stream.add_flag(new Flag()); } public override void detach(XmppStream stream) { stream.get_module(Presence.Module.IDENTITY).received_presence.disconnect(on_received_presence); stream.get_module(Presence.Module.IDENTITY).pre_send_presence_stanza.disconnect(on_pre_send_presence_stanza); stream.get_module(MessageModule.IDENTITY).received_pipeline.disconnect(received_pipeline_decrypt_listener); } public static void require(XmppStream stream) { if (stream.get_module(IDENTITY) == null) stream.add_module(new Module()); } public override string get_ns() { return NS_URI; } public override string get_id() { return IDENTITY.id; } private void on_received_presence(XmppStream stream, Presence.Stanza presence) { StanzaNode x_node = presence.stanza.get_subnode("x", NS_URI_SIGNED); if (x_node == null) return; string? sig = x_node.get_string_content(); if (sig == null) return; new Thread (null, () => { string signed_data = presence.status == null ? "" : presence.status; string? key_id = get_sign_key(sig, signed_data); if (key_id != null) { stream.get_flag(Flag.IDENTITY).set_key_id(presence.from, key_id); Idle.add(() => { received_jid_key_id(stream, presence.from, key_id); return false; }); } return null; }); } private void on_pre_send_presence_stanza(XmppStream stream, Presence.Stanza presence) { if (presence.type_ == Presence.Stanza.TYPE_AVAILABLE && signed_status != null) { presence.stanza.put_node(new StanzaNode.build("x", NS_URI_SIGNED).add_self_xmlns().put_node(new StanzaNode.text(signed_status))); } } private static string? gpg_encrypt(string plain, GPG.Key[] keys) { string encr; try { encr = GPGHelper.encrypt_armor(plain, keys, GPG.EncryptFlags.ALWAYS_TRUST); } catch (Error e) { return null; } int encryption_start = encr.index_of("\n\n") + 2; return encr.substring(encryption_start, encr.length - "\n-----END PGP MESSAGE-----".length - encryption_start); } private static string? get_sign_key(string sig, string signed_text) { string armor = "-----BEGIN PGP MESSAGE-----\n\n" + sig + "\n-----END PGP MESSAGE-----"; string? sign_key = null; try { sign_key = GPGHelper.get_sign_key(armor, signed_text); } catch (Error e) { } return sign_key; } private static string? gpg_sign(string str, Key key) { string signed; try { signed = GPGHelper.sign(str, GPG.SigMode.CLEAR, key); } catch (Error e) { return null; } int signature_start = signed.index_of("-----BEGIN PGP SIGNATURE-----"); signature_start = signed.index_of("\n\n", signature_start) + 2; return signed.substring(signature_start, signed.length - "\n-----END PGP SIGNATURE-----".length - signature_start); } } public class MessageFlag : Xmpp.MessageFlag { public const string id = "pgp"; public bool decrypted = false; public static MessageFlag? get_flag(MessageStanza message) { return (MessageFlag) message.get_flag(NS_URI, id); } public override string get_ns() { return NS_URI; } public override string get_id() { return id; } } public class ReceivedPipelineDecryptListener : StanzaListener { private const string[] after_actions_const = {"MODIFY_BODY"}; public override string action_group { get { return "ENCRYPT_BODY"; } } public override string[] after_actions { get { return after_actions_const; } } public override async bool run(XmppStream stream, MessageStanza message) { string? encrypted = get_cyphertext(message); if (encrypted != null) { MessageFlag flag = new MessageFlag(); message.add_flag(flag); string? decrypted = yield gpg_decrypt(encrypted); if (decrypted != null) { flag.decrypted = true; message.body = decrypted; } } return false; } private static async string? gpg_decrypt(string enc) { SourceFunc callback = gpg_decrypt.callback; string? res = null; new Thread (null, () => { string armor = "-----BEGIN PGP MESSAGE-----\n\n" + enc + "\n-----END PGP MESSAGE-----"; try { res = GPGHelper.decrypt(armor); } catch (Error e) { res = null; } Idle.add((owned) callback); return null; }); yield; return res; } private string? get_cyphertext(MessageStanza message) { StanzaNode? x_node = message.stanza.get_subnode("x", NS_URI_ENCRYPTED); return x_node == null ? null : x_node.get_string_content(); } } }